Dangerous bacterial infections reach highest level in more than a decade in Canada

Annual cases of invasive meningococcal disease (IMD), a rare but dangerous bacterial infection, have reached the highest level seen in Canada in more than a decade.

This rapidly progressive disease is known to cause a number of serious complications, including meningitis – inflammation of the membranes surrounding the brain and spinal cord – as well as bloodstream infection, sepsis, severe organ damage, and even long-term disability or death.

Mortality rates are highest among infants and young adults, Federal data shows.

“This is a very significant outcome and a very serious disease at such a young age,” said Dr. Kristin Muecke, regional medical officer of health for Nova Scotia Health. “And so from that perspective, even though it’s rare, the consequences are quite high.”

While the annual matter matters dropped dramatically Following the rollout of meningococcal vaccines in the early 2000s — and they reaching record lows in 2021 amid widespread restrictions for the COVID-19 pandemic — recent Canadian public health data shows a steady return of IMDs.

According to data from the Public Health Agency of Canada, there were 48 cases of IMD nationwide in 2021, 74 in 2022 and nearly 100 cases in 2023.

Preliminary provincial data compiled by CBC News shows a big jump since then, to at least 132 cases in 2024 and 155 cases in 2025 — the country’s highest numbers since 2012. At least 63 cases have also been reported in 10 Canadian provinces so far this year. Data were not requested from the three areas because numbers are typically low due to population size.

While the increase in IMD cases after the pandemic was no surprise to infectious disease expert Dr. Alison McGirr, given the range of diseases that have returned to normal levels in recent years, she said these bacterial infections are particularly challenging because of their severity.

The disease is also difficult to predict, McGirr said. This is due to different bacterial subtypes appearing at different levels in different provinces, leading to occasional outbreaks that appear out of nowhere.

“The worrying thing about invasive meningococcal disease is that there have been many changes in epidemiology over time … for which we don’t have good explanations,” said McGirr, a senior physician scientist with the Toronto Invasive Bacterial Disease Network at Mount Sinai Hospital.

---

‘Something doesn’t feel right’

According to IMD the death rate in Canada is 14 percentThe risk of fatal outcomes is highest among infants and young adults. Another 15 to 20 percent of people infected have long-term health effects such as hearing loss, amputation or neurological disability.

disease spreads through Neisseria meningitidisA common bacteria that is harmlessly transmitted by about one in 10 people. Six subtypes – meningococcal A, B, C, X, W and Y – are known to often cause aggressive forms of this infection.

In those cases, the bacteria manages to enter the bloodstream, bypassing the immune system and causing sudden, severe illness.

This is what Jason Frizza and Sandy Hilmarson told their daughter Leah, remembering the experience in April 2024. The 11-year-old girl was diagnosed with a basic ear infection, but just hours later, she developed a fever and worsening headaches, then repeated vomiting.

Frieza said, “We looked at him and… something didn’t seem right.”

The Thompson, Jr., parents took their daughter back to a nearby hospital.

Leah was later diagnosed with life-threatening bacterial meningitis and was flown to HSC Children’s Hospital – more than 650 kilometers away in Winnipeg – where doctors discovered she also had a blood clot in her brain.

Her parents said she spent 10 days in the hospital as medical teams gave her intensive treatment, including multiple MRIs and broad-spectrum antibiotics. Since then she has completely recovered.

“We’re grateful that they were able to identify what was happening,” Hilmarsson said.

Manitoba has seen higher-than-average cases of IMD over the past three years amid an outbreak of meningococcal W, largely affecting youth in Winnipeg and Indigenous communities in northern parts of the province.

In 2025, there were four deaths out of 23 cases, which is about five times the normal annual number. Manitoba health officials said in January.

While most provinces are not seeing any major increase in IMD, many other regions are also seeing a recent increase in infections and deaths.

Saskatchewan’s annual IMD case count is projected to increase from four in 2024 to 17 in 2025, with three infections reported so far this year, according to provincial data provided to CBC News.

Meanwhile, public health data in Ontario shows there were six fatal cases out of a total of 30 infections recorded in 2024, while preliminary data shows there were 39 cases in 2025 and another 42 cases so far this year.

In Quebec, there have been fewer than five deaths out of a total of 53 cases in 2024 — the province withheld the exact numbers for privacy reasons, with six deaths and 47 cases expected in 2025 and another 10 cases so far in 2026.

Different province, different strategy

McGirr, a Toronto infectious disease expert, said it’s not clear why some parts of the country, such as Manitoba, are seeing more cases than others.

The prevalence of the W subtype is also different in some parts of the province, he said. “Is it going to spread around the world? Is it specific to Manitoba for some reason? And the answer is: we don’t know.”

The province has changed its meningococcal vaccination strategy to deal with the outbreak, allowing children to receive a vaccine that covers four subtypes of meningococcal bacteria at one year of age. Before 2024, children had to wait until Grade 6 to get that shot, said Dr. Brent Roussin, Manitoba’s chief provincial public health officer. CBC Manitoba was recently told.

Currently, Canada recommends different vaccines that cover different bacterial subtypes – including a four-subtype shot that provides protection against meningococcal A, C, W and Y, and different vaccines that protect against subtypes B and C.

Meningococcal C vaccine is usually given to infants and young children, while the shot that protects against the four subtypes is usually given to all teenagers in high-risk groups or in some provinces.

Meningococcal B vaccine is usually only given to high-risk children, and again, its use varies between provinces – Some Canadian families forced to rely on private insurance or pay out-of-pocket to get the shot.

In Nova Scotia, vaccination strategies also changed in view of the 2022 IMD outbreak caused by meningococcal B. Due to which a student died at Dalhousie University.

Muecke, Nova Scotia Health’s regional medical officer of health, said the province has begun offering the meningococcal B vaccine at no cost to young adults living in congregate settings such as university dormitories or military barracks.

Muecke emphasized that given the significant differences in infection rates between IMD subtypes and regions, each province needs a tailored approach.

“While it’s instructive to look at what happens in other provinces and other countries… we have to be quite intentional about looking at what’s happening specifically in our region,” he said.

Vaccine uptake is declining

The overall uptake of meningococcal vaccines in Canada has also declined, adding another complication for health teams trying to manage this challenging disease.

Coverage of meningococcal C vaccine declined from more than 90 percent of children under two years of age in 2019 to less than 84 percent by 2024. Federal data shows.

Vaccination coverage for the four-subtype shot has also declined among adolescents since the pandemic.

“It is very concerning that our coverage rates have changed,” said Dr. Joanne Langley, a pediatric infectious diseases professor in the faculty of medicine at Dalhousie University in Halifax and senior medical director of Meningitis Foundation Canada.

Langley attributed the decline to several factors, including reduced access during the COVID-19 pandemic, vaccine hesitancy and a shortage of primary care providers in many areas.

Despite those obstacles — and the fact that no vaccine protects against all meningococcal subtypes — he stressed that these vaccines are the best way to protect children and young adults from developing IMD.

In the rare cases where young people contract this serious infection, many experts said it is important to know the warning signs and act fast, as someone’s condition can worsen in a matter of hours.

“It can start to look like many infections. You get a fever, you get a headache, you don’t feel well, you might get nauseous,” Muecke said. “But then, unfortunately, it can develop into a more serious condition very quickly.”

Red signals indicating a serious infection in the brain or blood may include severe headache, stiff neck, feeling sensitive to light, becoming confused or unusually sleepy, or a rash all over the body.

“Parents are the best advocates and understand best when something is wrong with their child,” Langley said. “So if your child is different – ​​if you’re concerned – try to get them the care they need.”